Rotary engine.



PATENTBD JULY 28, 1908.

J. W. VDN PITTLER.

ROTARY ENGINE.

APPLICATION FILED JUNE a, 1907.

a SHEETS-SHEET 1.

PATENTED' JULY 28, 1908.

J. W. VON PITTLERlv ROTARY ENGINE. APPLICATION FILED TUNE 6, 1907.

3 SHEETS-SHEET -2.

. 25 y, rollers arranged on the slides and running in UNITED STATES PATENT oEEroE.

JULIUS WILHELM VON PITTLER, OF BERLIN, GERMANY.

Specification ef Letters Patent.

Ro'rAnY ENGINE.

4Patented .iuiy 2e, 190s.

Application le. v.Tune 6, 1907. Serial N. 377,513.

.ins, forming apart hereof.

' tons an l blades or his invention relates to engines, pumps and the like in which there is a rotating member dprovided with sliding blades or piswhich blades are arranged to slide and in each of Whloh there is provided a fixed abutment which forms with the blades working-chambers within the grooves. l

According to the present invention the istons of mechanism of this kind are contro` ed by cam surfaces acting on their end surfaces. By this means it is possible with perfect guidingLto u se the spaces be'- tween the 4rotating member` and the casing as further working-chambers. To the known method of guiding the blades by means of cam-grooves in the casing, the method of v guidingabove mentioned is much to be preferred,since the rollers as well as their 1degrooves, in the rapid motion of the lades round the casing or cylinder, are subjected to such excessively rapid wear that this system of iding is practically useless.

he guiding of the blades or pistou-fin r0- tary engine, pump or the like mechanism on cam-surfaces on the casing is known per se,

but its application to a mechanism of the present kind, with working-chambers provided in annular grooves inthe rotating member, is new.

The invention further consists/in a special I arrangement of the grooves in the rotating member whichoiers material advantages. over the known arrangements, as will be seen hereinafter.`

f Figures 1 and 2 illustrate in longitudinal and transverse section respectively, one embodiment of the linven ion consisting ofa motor in which thepistons or blades are axially movable andare arranged between two parallel surfaces by which'they are moved `and. guided. Fig. 3 is a development of these surfaces, showing the eriphery of the i s. 4 and 5 are similar views in Whic the bla es are radially movable; 6 is a view similar to Fig. 4 inv having annular grooves athwart corresponding parts.

'inner fixed sleevesurrounding which the blades aremoved in both directions solely'by a fluid pressure medium, and l Fig. 7 is a development of still another form walls of the casing are provided with parallel curved surfaces 3, 4 'between which the pistons are arranged and by which they are moved and gulded. These surfaces form, with the rotary member and the istons, Working chambers 6, 7; assuming t at the rotary member and blades rotate in the direction indicated by the arrow 17 in Figs. 2 and 3, 8 and 10 'are the inlet ports and 9 and 11 are the outlet ports. 'L f In the periphery of the rotating member are out or otherwise formed one or more grooves 12 and athwart thesegrooves the piston-blades are arranged so as to slide transversely across the same as the ends of the blades travel upon the parallel surfaces 8 and 4. Within each groove is an abutment corresponding grooves as the piston or pistons reach and pass the abutments. is thus always between one of the blades and each end face of each abutment, a working chamber which varies with the movement of the blade. In the case of a pump the chambers situated on the right hand of the abutment (Fig. 3) will be ressure chambers andthose on the lleft han of the abutment will There be suction chambers and 14 and 15 will Abe res -ectively theinlet and outlet ports.

eferring to Figs. 4 and 5, the same reference Qharacters have been used as in describing tle form shown-in Figs. 1 to 3, to indicate grooves are turned concentrically in the end surfaces of the rotating member. Accordingly the blades are radiall movable `and the arallel surfaces 3, 4 are ormed, one on an the shaft of the rotating member and the ot er in the cylindrical portion of the casing. This arrangement presents considerab advantages as compared with the arrangement Vinwhich the oves are provided in the -peripheral surcoe of the rotating member and wherein the In Figs. 4 and 5 the Y l blades move axially. With a constant width niultiple-ex ansion engine, since. in conductprovide two sets of vouter ends of these widened ing the wor ing fluid through the concentric working chambers in the order i'roin the interior to the exterior, the successive working chambers'increase in capacity as required. This arrangement of the grooves is moreover of importance for motors of automobiles and generally for engines which are torun at varying speeds with the turning moment varying in inverse roportion. Assuming that the mechanism is used as a motor and that a con- Istant current of a iiuid under pressure is conducted through the mechanism and moreover that each groove of themechanism can be inserted separately into the fluid current, it is clear that the speed of rotation will be lower if a groove lying farther towards the exterior beqused as the working-chan'iber, while at thesame time the turning moment increases in accordance with the larger radius. Since two or more working chambers can also be used together in` difl'erent combinations, a large number of different speeds-can be obtained with correspondingly varying turning moments. A further advantage of the construction withr radially movable bladesconsists in that when controlling the blades by means of cam-surfaces arranged on the casin these surfaces are of simple curvature, whi e when employing axially movable 'slides the cam-surfaces are screw-shaped.

In the formshown in Figs. 4 and 5 it will be observed. (Fig. 5), that there are two sets of istons; one set at eachend of the machine. Vith this construction, the rotating member lis better balanced. Furthermore it will be noted that both sets are arranged symmetrically with respect to each other. It will be obvious, however, that it is not necessary to i pistons or to arrange both setssymmetrically.

In Fig. 6 there are no working chambers 6,

- -7A formed bythe istons,' 1Qtating member and easing, or by t e pistons, rotating .mem-

The ypistons ber and an inner fixed sleeve. are arranged to be moved wholly by a fluid pressure medium and do not travel upon any curved surface, as inthe case of the embodiments shown in Figs. 1 to 5 inclusive. For this pur ose, the inner ends 22 of the pistons are Vma e'slightly wider and the inner ortions 23 of the slots of the rotating mem er, in which the inner ends of the pistons work, are correspondingly widened( Into the ortions of the slots fluid pressure may e 'introduced through achannel 26 in such a way as to normallyhold the istons inwardly s0 that their openings w' not register With the grooves in the rotating member. Just before they reach the fixed abutments, however, they pass over the channel 26 and the inner ends of the widened portions of the piston slots are brought into communication with another channel .25 through which iiuid pressure is introduced behind the pistons in order to throw them outwardly and into such a position that the openings therein will register with the grooves aseach piston reaches and passes the abutment. As soon as each piston passes the abutmcnts, its slot again communicates with the channel 26 and the piston is pressed back into the slot.

ln rapidly rotating mechanism the slides maybe caused to move outward by the centrifiigalvforee, so that in some cases'thc action offthe iluid pressure supplied through the channel 25 can vbe dispensed with, or the iiiward movement could be impartedv to the piston by a constant pressure introduced into the space between the rotating member and the cylindrical casing. This pressure would of course be so regulated, as to. over.

come the centrifugal force but to be overcome by the intermittent*` pressure acting upon the inner faces of the widened parts of 'of pistons and in which there is a` fluid pressure medium for keeping each set of pistons in contact with the corresponding surface.

A central channel 20 supplies pressure to both y sets of istons and each piston in one set is preferallily provided with a shoulder or rojection 2l which, when the corresponi ing pistons in each set are forced inwardly by the surfaces, abuts closely against the opposite.

piston. In this way the pressure of the fluid medium upon the pistons may be reduced, while they ass the abutments.

It will beseen t iat in all the forms of the -mechanism withguiding-cam suiffces as blades. By this means 'wear of the mechai'i-v above described, the said cam-surfaces are so arranged that there is no relative motion between the rotating member and each blade during the time that the said blade is su porting the pressure of the driving fluid in .the

case of a motor or of the driven iiuid in the case of a pump. For this purpose in the arrangement shown in Figs. 1-3 and 7 the parts of cam-surfaces bounding the wide lparts of the chambers 6 and 7 are parts' of circular ring surf-aces lying in. planes perpendicular to the axis of rotation of-the rotating member, see Fig. 3. Also in Figs. 4 and 5,

the cams 3 and 4 have surfaces concentric to the axis of the rotating member at the places Where there is unbalanced pressurev on the ism is reduced to a minimum especially when working under heavypressures. It is obvious however that the said blades may be arranged to'be moved when under pressure, for example, in certain kinds of air-compressors where low pressures are employed.l

Various changes may be made in the several constructions illustrated and various other embodiments of the improvements may be had, Without departing from the spirit of the invention.

It will be understood that any suitable Huid pressure medium may be employed and that the improvements may be applied to all forms of motors or pumps Without limitaj tion. -It will also b e understood that the particular number of pistons illustrated in the accompanying drawings is arbitrary and not essentlal.

I claim as my invention: 1. In a rotary engine, the combination of a rotary member'having a groove, a fixed abutment therein, a iston adapted to slide across thegroove and having an opening so as to be capable ofpassin the abutment and a casing having a cam su ace upon which the piston travels with one of its end faces..

2. In a rotary engine, the combination of a rotary member having a groove, an abutment therein, a sliding piston athwart the groove and havin an opening so as to be cagable of passing t e abutment, and a casing aving a surface upon lwhich the piston t e grooves as the travels and adapted to form with the rotary member and piston a Working chamber.

3. In a rotary engine, the combination of a rotary member having a groove, an abutment therein, a sliding piston athwart the groove, and parallel surfaces between which the piston is guided, said piston having an o ening Whichis brought into register with piston reaches and passes the abutment.

4. In a rotary engine, the combination of a rotary member having concentrically arranged grooves in one end surface, fixed abutments therein, a piston adapted to slide radially across the grooves and having openings therein and means to bring the openlngs into register With the grooves as the piston reaches and passes the abutments.

5. In a rotaryengine, the combination of a rotary member having concentrically arranged grooves in both end surfaces, ixed abutments therein, pistons ada ted to slide radially across the grooves and aving openings therein, and means to bring ings into register with the grooves asthe pistons reach and pass the abutments.

In testimony whereof Ihave signed my name to this specification, in the presence of two subscribing Witnesses.

JULIUS WILHELM VON PITTLER.

Witnesses:

WOLDEMAR HAUPT, HENRY HASPER.

the opensov 

